The present invention relates to a bandage having internal components that record, process, store and/or deliver information concerning the usage of the bandage. More specifically, the invention relates to an eye patch that includes a microcontroller which records, processes, and delivers information concerning the times the eye patch was worn by a patient.
Amblyopia, often referred to as "lazy eye", generally refers to poor vision in one eye as a result of improper development during infancy and childhood. Amblyopia is the most common vision defect of childhood, occurring in approximately 1%-5% of the population. Amblyopia can be caused by any condition that affects normal bilateral usage of the eyes and normal visual development during childhood. In many cases, the conditions associated with amblyopia may be inherited. The most common cause of amblyopia is a misalignment of the eyes because of muscle problems. Other causes include significant differences in focusing between the two eyes, high amounts of astigmatism, retinal defects, and other visual disorders such as cataracts. Generally, amblyopia occurs when the child relies exclusively on his or her better eye for vision. For example, when the child has one crossed eye because of muscle problems, the crossed eye effectively "turns off" to avoid double vision, resulting in the child using only the better eye. As use of the crossed eye diminishes, the muscles and parts of the brain required for its normal function weaken, reinforcing the amblyopia, as a feed-forward process.
If amblyopia is detected early in the child's development, treatment is often very effective (success rates up to 93%) in correcting the amblyopia. The best approach to manage amblyopia is to detect the disfunction before the age of two and break the feed-forward spiral of amblyopic disuse. If amblyopia starts, it can most effectively be cured if children are adequately treated before the ages of six to seven years. To correct amblyopia, a child must be made to use the weak eye instead of relying only upon the strong eye. This is done by occlusion therapy, which involves patching or covering the strong eye for several hours during the day, often for weeks to as long as years, to force the weak eye into usage.
In order to treat amblyopia, a critical factor is patient compliance. Since amblyopia must be treated when children are under the age of six, it is often difficult for the physician to determine whethe r the patient is following the prescribed occlusion therapy. In some studies, the patient compliance rate has been found to be around 50%. Thus, although specific patching regimes can be prescribed, until now, their effectiveness has been difficult to determine. Presently, patient compliance is typically measured by clinical attendants or by a parental occlusion log book which details the amount of time a child is wearing the eye patch. While an occlusion log book is an attempt to monitor occlusion, it suffers from several weaknesses, such as bias of the third-party recorder and the inability to monitor the patient for the entire duration of the therapy.
Recently, an occlusion dose monitor (ODM) has been developed to help the physician more accurately determine patient compliance. The ODM is a portable datalogger that can measure the time an eye patch is in contact with the skin by means of a reduced resistance between two miniature electrocardiogram electrodes. The datalogger is worn in a shoulder bag by the patient and includes a pair of leads connected between the datalogger and the eye patch. When a patient is wearing the ODM, the physician can recover information from the datalogger as to when the eye patch was worn, giving the physician an objective measurement of how accurately his therapy has been followed. Before the ODM, it was not possible for the physician to distinguish between poor patient compliance and physiologic non-responsiveness to occlusion. By using an ODM, however, the physician can objectively monitor the period of time the eye patch was worn by the patient and adjust his dose accordingly.
Although the discussed ODM has been used to measure patient compliance, the datalogger contained in a shoulder bag is cumbersome and inconvenient for an otherwise active child to use, especially if occlusion therapy is prescribed for an extended continuous period of time. Additionally, the externally worn datalogger is subject to physical damage when worn by a young child who is active or unconcerned with preventing damage to the datalogger. Finally, the datalogger can draw abnormal attention to the young patient, which increases the patient's resistance to treatment. Thus, it is readily apparent that a compact bandage or eye patch which includes small and unobtrusive components that can accurately record and store data concerning the status of the bandage and the patient would be a great advantage.